1. Field of the Invention
The present invention relates to a transport system including a transport device arranged to lower an article to a load port and a set-up method for the same.
2. Description of the Related Art
There is a known transport device arranged to lower a transported article to a load port onto which the article is to be loaded (e.g., see Japanese Laid-open Patent Publication No. 2002-270660 (FIG. 1)). Japanese Laid-open Patent Publication No. 2002-270660 describes a case in which a transport device lowers a transported article to a load port provided on a manufacturing apparatus. The transported article undergoes various manufacturing processes after it is loaded onto the load port of the manufacturing apparatus. In order for the article to be properly processed by the manufacturing apparatus, the article must be placed precisely at a prescribed position on the load port of the manufacturing apparatus.
Consequently, in some cases, positioning means such as positioning protrusions and positioning holes are provided on/in the transported article and the load port in order to position the transported article with respect to the load port in a horizontal direction (e.g., see Japanese Laid-open Patent Publication No. 2009-105109 (FIG. 2)).
In order for a transport device to precisely position a transported article with respect to a load port using the kind of positioning means disclosed in Japanese Laid-open Patent Publication No. 2009-105109, it is necessary to precisely set the position to which the article will be lowered by the transport device in advance. When a transported article is loaded to a load port of a manufacturing apparatus as explained above, it is imperative to accomplish this kind of precise positioning in order for the article to be properly processed by the manufacturing apparatus.
In order to improve the transport efficiency of an entire article transport process, it is common to provide temporary placement locations for temporarily storing a transported article. If it is necessary to set the position of an article at the temporary placement location as precisely as that at the manufacturing apparatus, an excessive amount of work may be required to install the entire transport system.